Loans and Other Real Estate - Lakeland's Non-Accrual Loans and Leases and Its Accruing Troubled Debt Restructurings (TDRs) (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total non-accrual loans	$ 21,138	$ 12,130
Other real estate and other repossessed assets	563	830
Total non-performing assets	21,701	12,960
Financing Receivable, Modifications, Recorded Investment, Still Accruing	5,650	9,293
Commercial, secured by real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total non-accrual loans	12,314	7,192
Commercial, industrial and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total non-accrual loans	1,539	1,019
Equipment finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total non-accrual loans	284	501
Real estate - residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total non-accrual loans	3,428	1,986
Real estate - construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total non-accrual loans	967	0
Home equity and consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total non-accrual loans	$ 2,606	$ 1,432